Harmful free radicals and reactive oxygen species have been implicated in aging and chronic diseases [1]. For instance, oxidative damage is particularly detrimental to the brain, where the neuronal cells are largely post-mitotic and those which are damaged cannot be replaced readily via mitosis [2]. During normal aging, the brain undergoes morphological and functional changes resulting in the observed neurobehavioural declines such as decrements in cognitive and motor performance, which leads to Alzheimer's disease (AD) and Parkinson's disease (PD) respectively. Prominent symptoms of Alzheimer's disease include memory loss and confusion, whilst common symptoms Parkinson's disease among others include trembling hands, arms, and face. It is understood that these symptoms are detrimental to the patient, particularly if appropriate medicinal relief is not provided.
Based on the above, various preventive measures which involve efforts to offer resistance against oxidative stress, including physical activity and dietary intervention, have been suggested to combat the advancement of chronic diseases as we age.
One of the effective resolutions which is evident based on studies conducted provides diets containing high amounts of phytochemicals, whereby activities in relation to protection against these free radical-induced diseases was observed, due to their high antioxidative activities [3]. Plant phenolics are especially important antioxidants because of their high redox potential, which allows them to act as reducing agents, hydrogen donors, singlet oxygen quenchers and metal chelators [3]. Antioxidants that accumulate in neuronal tissues are potential candidates for the prevention and treatment of neuronal disorders involving oxidative stress. Phenolic antioxidants may or may not cross the brain barrier, depending on their properties, such as charged state, lipophilicity and interactions with efflux transporters, with possible relative specificity of the compounds for different brain areas [4]. For example, proanthocyanidins from blueberries may be found in the striatum while ellagitannins from strawberries may involve the hippocampus [5]. Many studies have recently shown that plant phenolics are able to enhance cognitive performance, through their ability to reduce oxidative stress [2, 5-12].
In view of the above, it is clear that there is a need for an antioxidant composition preferably based on plant extract(s) which is able to provide significant neuroprotective effects and thus improve cognitive performance.
It is therefore a primary object of the present invention to fulfil this need and in particular to provide an effective method for prevention of neurodegenerative ailments in addition to improving cognitive performance due to oxidative stress.
On the basis that oil palm phenolics possess significant antioxidative activities [13, 14], it is hypothesized that they may have significant neuroprotective effects in vivo. Experiments were conducted on a balb/c mice on a normal diet fed with oil palm phenolics for six weeks for observation and thus verify the signs of improvement in brain functions.